1. Field of Invention
The present invention relates to the use of a computer and computer printer to print a scale and/or conversion instrument used to prepare and interpret scaled drawings, maps, aerial photographs, graphs and similar documents. In it""s major embodiment, the present invention particularly relates to the fast and economical production of a scale instrument which is matched or calibrated to the same scale as a drawing, map, graph, or similar document, the scale of which has been enlarged or reduced from the original; or to the same scale as an aerial photograph or other image which has not been printed at a specific predetermined scale. The tasks performed with this scale instrument would otherwise be more costly and subject to significant error because of the time and care necessary to fabricate, on a case by case basis, a manually produced scale instrument which matches the scale of each of such documents. The instruments printed by the present invention also can be calibrated in the same scales as the engineer""s and architect""s scale instruments typically used for producing scaled drawings of all types,
In other embodiments, the present invention can also produce a conversion instrument denominated in a different measuring system than that used to produce the drawing, thus allowing the easy conversion to alterative systems of measurement such as from the English system to Metric. The process also can produce an instrument containing one or more scales which allows the conversion, without additional measurement or calculation, of units of distance into units of another system such as area units or monetary units, or into units of any other measuring system where the total units in such system has a direct relationship with the total distance measured on the drawing. As one example, the process can print a scale instrument to be used in estimating the acreage in a 100 foot wide railroad right of way using a map scaled at 1xe2x80x3=154xe2x80x2. In such an instrument, each linear inch would be equivalent to 15,400 square feet or 0.35 acres, and the one acre index mark would be 2.83 inches from the xe2x80x9c0xe2x80x9d index mark, the two acre index mark would be 5.66 inches from the index and so on, with intermediate index marks between such major index marks. Such an instrument can be printed with one or more scales which can be used by folding the media along the base line of each such scale so that the base line can be placed on and manipulated across the drawing. Continuing the example, if land in the area shown by the map were worth $10,000 per acre, the value of land within the right of way could be estimated with a scale instrument denominated in dollars per acre. In this case, a mark at 2.83 inches from the index would also indicate that the dollar value of land in a corridor 100 feet wide extending from the index mark to that point is equal to $10,000. Such dollar denominated index marks would be extended along the scale, together with intermediate index marks. In addition, the scale instrument can be printed on media which was flexible enough to be folded and unfolded such that multiple scales could be printed on one sheet of media, one indicating, for example, distance, another acreage, and yet another dollar value so that each of these factors could be read with the same instrument by folding and unfolding the printed media so as to expose the appropriate scale. It is obvious that there are many more examples of situations where the instrument can be used in determining useful information which is mathematically correlated to a distance within scaled drawings, maps, aerial photographs, graphs and similar documents.
2. Description of Prior Art
Cartographers, architects, engineers, and others have traditionally prepared drawings which graphically represent full sized objects by a process in which a dimension measured on the full sized object is represented by a fraction or multiple of that measurement on the drawing. The mathematical relationship between the two units is generally known as the xe2x80x9cscale.xe2x80x9d Different professions use different measurement systems and label their scale instruments differently (e.g. cartographers may indicate scale as 1xe2x80x3=1 mile, or 1:25,000, engineers may use 1xe2x80x3=40xe2x80x2, architects may use xc2xcxe2x80x3=1xe2x80x2, etc.). Scale instruments to assist the drafting and interpretation of scaled drawings, etc. are well known to those who practice the art. One of the most common is a triangular scale instrument constructed of wood, plastic, metal, or similar material which features six faces, each denominated in a different scale. Such scale instruments are manufactured with scales commonly used by civil engineers, scales commonly used by architects, and metric scales. Flat ruler-like instruments with one or two common scales are also available in various configurations. More recently, CAD (Computer Assisted Drafting) programs have all but eliminated the need for the use of a scale instrument in the preparation of many scaled drawings since that functionality has been integrated into the CAD programs. Scale instruments, however, continue to be employed extensively by users of scaled drawings, maps, aerial photographs, graphs and similar documents.
Recent technology has allowed drawings, etc., which have been created on one size of media to be readily converted to another size, often via other media such as microfilm or computer image files. Thus, drawings and maps prepared and plotted on large sheets of paper are regularly reduced to 11xe2x80x3=17xe2x80x3 or 8xc2xdxe2x80x3=11xe2x80x3 or other size sheets of media by such means as changing the print parameters in a CAD program, scanning a document and converting the image into a computer file, or publishing the drawing in proprietary computer file formats such as Adobe Corporation""s Acrobat program. Modern office copiers have the ability to shrink or enlarge an image. While the scale of the drawings is changed by such actions, normally the relative spatial relationship between the vertical and horizontal dimensions of the drawing remains intact. Therefore, where the length of one dimension in the full sized object is known, the length of the corresponding line in the revised drawing can be measured and the revised scale ratio determined by calculation as follows:
Revised Scale=Distance Represented by the Line/Measured Length of a Drawn Line
Knowing the revised scale ratio, the user can determine the length of any dimension in the full sized object by measuring the corresponding dimension in the revised scale drawing and solving the equation as follows:
Distance Represented by the Line=Measured Length of a Drawn Line * Revised Scale
Even in those cases where the vertical and horizontal dimensions are changed by differing amounts, the user can determine the new scale for lines on the x axis, for lines on the y axis, and for lines having various bearings between the x and y axes with the number of additional scale instruments being interpolated based on the need for accuracy.
Where the reduction or enlargement of the drawing is an exact multiple of the original scale, a common scale instrument calibrated in that multiple of the original can be used to read distances represented by lengths of the various lines on the drawings. For example, if a drawing in which 1xe2x80x3=200xe2x80x3 is reduced from 22xe2x80x3=34xe2x80x3 to 11xe2x80x3=17xe2x80x3, a factor of one half, a scale instrument calibrated at 1:40 can be used to interpret the drawing. However, since the most common scale instruments using these units of measurement are denominated in 1:10, 1:20, 1:30, 1:40, 1:50, and 1:60, a drawing prepared such that 1xe2x80x3=40xe2x80x3 and which has been reduced by half cannot be as easily interpreted with the common instrument. In practice, it is typical to use the 1:40 scale on the common scale instrument and double the reading, either mentally or by the use of actual calculations. However, this practice slows the user and error can be introduced.
These difficulties become much more pronounced when the size of the drawing is changed by an uneven factor which typically occurs when, for example, a drawing is microfilmed and then a print is made from the film, or when a computer image or portion of a computer image is printed. Moreover, the image may be reprinted in a different media size than the original. These practices lead to situations where, for example, a drawing originally prepared in a scale of 1xe2x80x3=40xe2x80x2 will end up with a scale of, say, 1xe2x80x3=724xe2x80x2 or some other uncommon scale. No commercially available scale instrument is calibrated in this denomination nor would it be calibrated in the many various other uncommon scales which would be necessary to match other reduced scale drawings. To interpret such a drawing, a careful artisan must first determine the scale as indicated above, and then calculate the length of 10 units or 100 units or some other convenient measure and mark off multiples such units on the edge of a paper, wooden stick, or other convenient media. If prepared accurately, this ad hoc scale instrument can be used to estimate the real world dimensions lines shown on that specific drawing. However, this is a tedious exercise with significant potential for error, especially if many such instruments need to be constructed to match a variety of scales on many different drawings. The difficulties are increased when three or more such instruments must be constructed to measure distances in drawings which have different scales on the x and y axes because of shrinkage (one instrument for the x axis, one for the y axis, and one or more instruments (depending on the accuracy required) to be used in estimating lines which are not parallel to either the x or y axis. Thus, the relevant fields of art includes not only instruments in the common scales, but instruments which yield the same functionality for drawings, etc., with uncommon scales.
A number of mechanical improvements on common scale design have been developed. Bennett et al.""s Variscale (U.S. Pat. No. 4,707,928) contains 17 scales which can be denominated in a variety of scale ratios. While having more scales at hand is an advantage over the common triangular scale instrument""s six, this and other similar improvements are of little use when the drawing has been reduced or enlarged to an uncommon or uneven scale, such as 1xe2x80x3=724xe2x80x2. The computer generated scale invention provides a far greater variety of scales, limited only the ability of the computer printer to produce a line distinct from an adjacent line on the media.
Christiansens""s Variable Scale (U.S. Pat. No. 2,156,524) represents a mechanical approach to the problem of working with drawings with diverse and uncommon scales. While it has some functionality with these drawings, it is inherently not as accurate as the subject invention in determining the actual scale. The user of the Christiansen device must interpolate from scales notations marked on the sides of the device""s movable ribbon. In addition, it is physically more cumbersome than the invention and is subject to wear in use and resultant inaccuracy. Additional potential for error accrues if the user desires to compare or modify one drawing based upon data from other drawings, when more than one is at an uncommon scale. This common task requires the practitioner to measure on one or more drawings and transfer information to the final drawing, sometimes moving back and forth between various drawings several times to plot data. Christiansen""s device requires that it be re-calibrated for each such drawing by laying it against a line in the drawing and matching the known length of the line in the real world to the applicable mark on the instrument. The current invention prints scale instruments in the exact scale necessary so that the same instrument with the exact same scale can be used with the specific drawing each time it is needed.
Yu""s Universal Scale (U.S. Pat. No. 5,896,671) can be used to determine distances on a scaled drawing which has an uncommon scale, albeit with considerable manipulation. This device does not allow the direct reading of distances on a scaled drawing, rather requiring that the user determine the number of major and minor index lines which are crossed when the device is laid out along a line which is to be measured. Then the user must determine the distance represented by each of the major and minor lines, ascertain the number of major lines crossed and the number of minor lines crossed after the final major line, and then multiply the number of major lines by the distance they represent and the number of minor lines by the distance they represent and add the two sums. This process is time consuming, cumbersome and the potential for error is not insignificant. Like Christiansen""s Variable Scale, this device must be recalibrated for each drawing which is analyzed and must be set and reset when working with two or more drawings with uncommon scales at the same session.
Duffield""s Image Size Measuring Device (U.S. Pat. No. 5,400,513) is a mechanical device for estimating the size an object in medical diagnostic images in which objects are not shown at their true size. It""s operation is based on the knowledge of the true size of at least one object in the image. It""s simplicity of operation in the primary embodiment is offset by the fact that considerable interpolation is required. An alternative embodiment allows a more accurate estimate, but with the disadvantage of requiring that the user hold movable parts of the device together as it is transferred from one object to another. This requires dexterity and introduces considerable potential for error. In addition, accurately estimating the size of an object which is significantly larger than the index object would require that the device be physically large. Since there is no conceptual difference between a medical diagnostic image in which the actual size of one object is known, and for example, an aerial photo in which the true dimension of at least one object is known, the present invention allows more accurate estimate of size without the disadvantage of moveable parts which can be inadvertently displaced.
More recently developed are several electronic devices (Woo, Jr. et al., Electronic Rule For Precise Distance Measurement And Distance Setting, U.S. Pat. No. 4,158,229; Parhiskari Programmable Display Engineering Scale, U.S. Pat. No. 4,839,833) and electromechanical devices (Buerner, Multipurpose Drafting And Measuring Instrument, U.S. Pat. No. 4,184,261, Robinet, Electronic Drafting Instrument With Digital Readout Of Displacement, U.S. Pat. No. 4,246,703; Logan et al, Automated Measuring Scale, U.S. Pat. No. 4,435,904) which can be used to prepare, modify, and interpret drawings at uncommon scales. When working with uncommon scale maps, each of these devices has one or more deficiencies relative to the present invention. First, all are inherently more expensive to manufacture than the present invention. Second, they can be presumed to be more prone to failure and/or damage because of the nature of their materials and construction. Third, none have the advantage of the subject invention when the user needs to measure a distance or distances in one or more drawings which have irregular scales and transfer such distance information to another drawing which also may have an irregular scale. In that case, the unique and irregular scales must be ascertained and entered each time the instrument is used on another drawing. It is clear that recalibrating the scale for each separate operation is time consuming and introduces considerable potential for error. The present invention deals with this problem by printing a new sheet of media with a scale set at the irregular scale for a particular drawing, which sheet will be used each time data from that drawing needs to be obtained. Moreover, it is possible to write identifying information on the media and/or to allow the user to label the media from the computer user interface. With many types of media, the user can to make pencil marks on the sheet to show the extent of a line, thus creating the ability to verify the interpretation of the data. As an auxiliary benefit of the subject, the media sheets can be readily stored with the drawing in a file so they are available for future use and allow continuity between uses in a precise manner. Also, the scale instruments created by the subject invention can be readily carried to the field and used under adverse working conditions. This is not true of the electromechanical devices which need to maintain precise contact with the drawing to maintain accuracy. Finally, the Parhiskari device anticipates the use of a relatively few number of pre-defined scales.
The present invention uses a computer and printer to produce scale instruments denominated in a variety of scale ratios. Such instruments are especially useful for interpreting scaled drawings, maps, aerial photographic, graphs, etc. which are not to one of the commonly used scale ratios.
Object and Advantages
The principal object of the invention is to provide a means, using a computer and computer printer, to generate a printed scale instrument in a large variety of scales to be used in interpret scaled drawings, maps, aerial photographic, graphs, etc. which have an internally consistent scale which is uncommon and which is not one of the scales typically used by practitioners. Inherent in the invention is a mechanism to calibrate the program to a variety of computer printers, a routine to quickly and easily calculate the inherent scale based on data within the document, the ability to use the printed scale instrument as a tool to convert lengths on a drawing in one measurement system another measurement system, and the ability to create scale instruments having multiple scales denominated in alternative systems when the printed media is transparent or can be folded.